product restructuring, exports, investment, and growth...
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Product Restructuring, Exports, Investment, and
Growth Dynamics
(Job Market Paper)
Leilei Shen ∗
September 24, 2011
Abstract
This paper estimates a dynamic general equilibrium model of entry, exit, and endogenous pro-ductivity growth. Productivity is endogenous both at the industry level (firms enter and exit)and at the firm level (firms invest in productivity-enhancing activities). The focus of the paperis on two activities that make productivity-enhancing investments more attractive, namely, ex-porting and product-mix choices. A firm that increases its exports and/or its number of productswill have higher sales – and this makes investing in productivity more attractive because thereare more units (sales) across which the productivity gains can be applied. These insights aretaken to firm-level Spanish data. We compute the Markov Perfect Equilibrium using a nestedpseudo maximum likelihood estimator (NPL) with dynamic programming algorithms. Threekey findings emerge. First, there is no evidence of learning by exporting: the observed positivecorrelation between exporting and productivity operates entirely via the impact of exportingon productivity-enhancing investments. Restated, exporting decision raises productivity, butonly indirectly by making investing in productivity more attractive. Second, there is evidenceof learning by producing multiple products: product-mix raises productivity directly in additionto the investment channel. Third, there are strong complementarities among the product-mix,exporting and investment decisions. Finally, we simulate the effects of reductions in foreigntariffs. This increases exporting, investing, and wages; and wage increases decrease the numberof product produced per firm and force the least productive firms to exit. Productivity risesat the economy-wide level both because of the between firm reallocation effect and because ofwithin firm increases in productivity.
Keywords: heterogeneous firms, endogenous product range, dynamic discrete games, contin-uous games, multiple equilibria, pseudo maximum likelihood estimation, entry, exit, and growthin monopolistic competition
JEL Classifications: F12, F13, F14, L11, O31, O33.
∗PhD Candidate, Department of Economics, University of Toronto, 150 St. George Street, Toronto, OntarioM5S 3G7, Canada. Email: [email protected]. I would like to thank Daniel Trefler, Victor Aguirregabirial,Loren Brandt, John Sutton, and Peter Morrow, for their invaluable guidance and insightful conversations, and theparticipants of the University of Toronto Economics Seminar for helpful comments. All remaining errors are mine.
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Introduction
Gains from trade through both comparative advantage effects and intra-industry resource re-
allocations have been examined intensively in the past ( Melitz (2003) and Bernard et al. (2003)).
One element that is missing from this literature is the existence of multi-product firms that under-
take investments that lead to higher productivity, a higher propensity to export, and more products
produced. While multi-product firms that invest dominate international trade, comparatively little
research examines their production and export decisions and their productivity trajectory or how
these decisions are influenced by globalization.
A large empirical literature has emerged over the past decade trying to determine the causal
relationship between productivity and exporting. Much of it documents the self-selection of more
productive firms into the export market. The evidence that exporting raises productivity growth
rates is less uniform, with some studies (Clerides, Lach, and Tybout (1998), Bernard and Jensen
(1999), Bernard and Wagner (1997), Delgado, Farinas, and Ruano (2002) and Bernard and Jensen
(2004)) finding no such effect, and others finding varying degrees of support for a positive ef-
fect of exporting on productivity (Aw, Chung, and Roberts (2000),Baldwin and Gu (2003), Van
Biesebroeck (2004), Lileeva (2004), Hallward-Driemeier, Iarossi, and Sokoloff (2005), Fernandes
and Isgut (2006), Park et al. (2006), Aw, Roberts, and Winston (2007), De Loecker (2010) and
Lileeva and Trefler (2007)). Two theoretical papers, Atkeson and Burstein (2007) andConstantini
and Melitz (2008), have formalized how trade liberalizations can increase the rate of return to a
firm’s investment in new technology and thus lead to future endogenous productivity gains. Both
papers share several common features: first, productivity is the underlying state variable that dis-
tinguishes heterogeneous producers; second, productivity evolution is endogenous, affected by the
firm’s investment decisions; and third, they each identify pathways through which export market
size affects the firm’s choice to export or invest.
Very little research has focused on the combination of investment, exporting and multi-product
decision in a general equilibrium framework. This paper develops a tractable dynamic general equi-
librium model of endogenous product selection and productivity growth that offers a natural and
intuitive explanation for key features of the Spanish firm level data. Our model and empirical anal-
ysis demonstrate the importance of firm and industry endogenous productivity growth in response
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
to trade liberalization. In every period, firms make decisions about entry and exit, investment,
number of products, and exporting, and compete in a monopolistic competition product market.
Following Bernard, Redding, and Schott (forthcoming) which builds on Melitz (2003), we allow
firms to produce multiple products of varying profitability. We assume firm profitability in a par-
ticular product increases with two stochastic and independent draws in the first period the firm
operates. The first is firm productivity, which is drawn stochastically after the firm enters and
pays the sunk fixed entry cost. This governs the amount of labor that must be used to produce a
unit of output. Firm productivity becomes a state variable in all subsequent periods and evolves
over time based on firm investment and random shocks and/or depreciation. The second is firm-
product consumer tastes drawn every period, which regulate the demand for a firm in a market.
We assume both draws are revealed to firms after incurring a sunk cost of entry. If firms decide
to enter after having observed these draws, they face fixed and variable costs for each good they
choose to supply to a market as well as a fixed cost of serving each market that is independent
of the number of goods supplied. We assume consumers possess constant elasticity of substitution
preferences on the demand side as in Dixit and Stiglitz (1977). Demand for product variety de-
pends on the own-variety price, the price index for the product, and the price indices for all other
products. If a firm is active in a product market, it manufactures one of a continuum of varieties
and so is unable to influence the price index for the product. This implies the price of a firm’s
variety in one product market influences only the demand for its varieties in other product markets
through the price indices. Therefore, the firm’s inability to influence the price indices implies that
its profit maximization problem reduces to choosing the price of each product variety separately
to maximize the profits derived from that product variety. The structure of our model eliminates
strategic interaction within or between firms.
In this paper we develop an algorithm for computing the Markov Perfect Equilibrium (MPE)
similar to C. Lanier Benkard and Weintroub (2007a)1 and C. Lanier Benkard and Weintroub
(2007b). A nice feature of the algorithm is that, unlike existing methods, there is no need to place
a priori restrictions on the number of firms in the industry or the number of allowable states per
1C. Lanier Benkard and Weintroub (2008) define an oblivious equilibrium in which each firm is assumed to makedecisions based only on its own state and knowledge of the long-run average industry state, but where firms ignorecurrent information about competitors’ states. They showed that as the market becomes large, if the equilibriumdistribution of firm states obeys a certain “light-tail” condition, then the oblivious equilibrium closely approximatesMPE.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
firm. These are determined by the algorithm as part of the equilibrium solution. In the past,
for Ericson and Pakes (1995) type models, MPE are usually computed using iterative dynamic
programming algorithms (e.g. Pakes and McGuire (1995)).However, computational requirements
grow exponentially with the number of firms and possible firm produtivity levels, making dynamic
programming infeasible in many problems of practical interest. In this paper, we take a different
tack and consider algorithms that can efficiently deal with any number of firms in a monopolistic
competition setting. This is most closely related to Hopenhayn (1992) and Melitz (2003). As in
Hopenhayn (1992), the analysis is restricted to stationary equilibria. Firms correctly anticipate this
stable aggregate environment when making all relevant decisions. This becomes computationally
feasible for MPE computation with common dynamic programming algorithms. We also use nested
pseudo likelihood (NPL), a recursive extension of the two-step pseudo maximum likelihood (PML),
that addresses inconsistent or very imprecise nonparametric estimates of choice probabilities to
compute the MPE.
The reason to model the investment, multi-product and exporting decisions jointly is they
are dependent on each other. Firms cannot export or produce multiple products, or have a lower
probability of doing so, below a certain productivity cut-off. Therefore firms need to invest and
increase their productivity in order to export and produce more products. The return to investment
is higher for exporting and multi-product firms, which makes the probability that the firm will
choose to invest dependent on the firm’s export status and the number of products produced. This
paper estimates a structural model of endogenous entry, exit, exports, product restructuring and
investment to evaluate the role that fixed costs of operating, sunk entry costs, cost of investment
and trade liberalization play in explaining the observed cross industry heterogeneity. Olley and
Pakes (1996) show that ignoring endogenous market exit can generate significant biases in the
estimation of production functions. The estimation of structural models of market entry is based
on the Principle of Revealed Preference. In the context of these models, this principle establishes
that if we observe a firm operating in a market it is because its value in that market is greater than
the value of shutting down and putting its assets to alternative uses. Under this principle, firms’
entry decisions reveal information about the firm’s underlying latent profit (or value). The same
for firms exit decisions.
Since our data do not provide firm-product-destination export information, we simplify the
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
demand parameter in Bernard, Redding, and Schott (forthcoming) to firm-product level only.
However, it is very simple to model the demand parameter in firm-product-destination level. The
main results of this paper should still hold with data that support this kind of model.
The model yields a rich set of predictions on productivity, investment, product restructuring
and exporting. First, firms self-select into exporting, investment, and range of products based
on their current productivity. Productivity evolves over time and is endogenous and positively
impacted by both investment and number of products produced. The direct positive impact on
productivity from the number of products produced suggests learning by doing. However, there
is no evidence of learning by exporting: the observed positive correlation between exporting and
productivity operates entirely via the impact of exporting on productivity-enhancing investments.
Past exporting is correlated with current productivity via past investing; that is, past exporting
complements past investing which leads to current productivity gains. Second, there are strong
complementarities among exporting, range of products and investment decisions. A rise in the
number of products raises productivity by making investment more attractive. (There is also a
direct impact of the number of products on productivity, which we conjecture captures unmeasured
investments in new products). Finally, we simulate the effects of reductions in foreign tariffs. This
increases exporting, investiment and wages; and wage increases cause a reduction in the number of
products per firm and force the least productive firms to exit. Productivity rises at the economy-
wide level both because of the between firm reallocation effect and because of within firm increases
in productivity
The rest of paper is organized as follows. In Section 1 we outline the dynamic industry model.
In Section 2 we define and solve for MPE. In Section 3 we discuss the data used and the limitations to
the data. In Section 4 we provide our main result, namely, the role that product differentiation, fixed
costs of operating, sunk entry costs, cost of investment and trade liberalization play in explaining
the observed cross industry heterogeneity. In Section 5 we discuss the counterfactuals. Finally,
Section 6 presents conclusions, policies and a discussion of future research directions. All proofs
and mathematical arguments are provided in the Appendix.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
1. The Model
Consider a world consisting of many countries and many products. Firms decide whether to pro-
duce, what products to make,and where to export these products. Products are imperfect substi-
tutes of each other, and within each product firms supply horizontally differentiated varieties. For
simplicity, we develop the model for symmetric products and n symmetric countries.
1.1. Static Model
1.1.1. Consumers
The world consists of a home country and a continuum of n foreign countries, each of which is
endowed with Ln units of labor that are supplied inelastically with zero disutility.
Consumers prefer more varieties to less and consume all differentiated varieties in a continuum
of products that we normalize to the interval [0,1]. The utility function of a representative consumer
in country j is given by:
U =
[∫ 1
0Cνjkdk
]1/ν
, 0 < υ < 1, (1)
as in the standard Dixit and Stiglitz (1977) form, where k indexes products. Within each product, a
continuum of firms produce horizontally differentiated varieties of the product. Cjk is a consumption
index for a representative consumer in country j for product k and is of the form:
Cjk =
[∫ n+1
0
∫ω∈Ωijk
[λjk (ω) cijk (ω)]ρ dωdi
]1/ρ
, 0 < ρ < 1, (2)
where i and j index countries, ω indexes varieties of product k supplied from country i to j
and Ωijk denotes the endogenous set of these varieties. Similar to Bernard, Redding, and Schott
(forthcoming) the demand shifter λjk (ω) captures the strength of the representative consumer’s
tastes for firm variety ω and reflects demand heterogeneity. λjk (ω) can also be interpreted as the
quality of variety ω. We assume σ ≡ 11−ρ > κ ≡ 1
1−ν or the elasticity of substitution across varieties
within products is greater than the elasticity of substitution across products and σ is the same for
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
all products. The corresponding price index for product k in country j is:
Pjk =
[∫ n±1
0
∫ω∈Ωijk
(pijk (ω)
λijk (ω)
)1−σdωdi
] 11−σ
. (3)
Furthermore, countries are also symmetric, and the only difference between the domestic market
and each export market is that a common value of trade costs has to be incurred for each export
market. Therefore, instead of indexing variables in terms of country of production, i, and market of
consumption, j, we distinguish between the domestic market, d, and each export market, x, except
where otherwise indicated.
1.1.2. Production
The only factor of production is labor as in Melitz (2003). The potential entrants are identical
prior to entry. A potential entrant who decides to stay out of the market gets zero profits. If
the firm decides to enter, it must incur a sunk entry cost fEN,i > 0 units of labor in country i.
fEN,i = fEN,i + εEN,it at time t, where fEN,i is the component of entry cost that is common to
all the firms in the market in country i, and εEN,it is a firm-specific component which is private
information to the firm, has zero mean, and is i.i.d. over firms and over time. Similar to Bernard,
Redding, and Schott (forthcoming) we augment the model to allow firms to manufacture multiple
products and to allow for demand heterogeneity across products. The new entrant is not active
until the next period. Furthermore, the initial quality and the product attributes that influence
demand (consumer tastes λ) of a new entrant are uncertain when the firm makes its entry decision,
and they are not realized until the next period. The initial productivity ϕ is common across all
of a firms’s products and is a random draw from the probability function g(ϕ) with cumulative
distribution function G(ϕ).Consumer tastes for a firm’s varieties, λk ∈ [0,∞), vary across products
k and are drawn separately for each product from the probability function z(λ) with cumulative
distribution function Z(λ). To make use of law of large number results, we make simplifying
assumptions that productivity and consumer tastes distributions are independent across firms and
products, respectively, and of one another.
Once the sunk entry cost has been incurred in period t− 1, the potential entrant enters at the
end of period t− 1 and becomes an incumbent in period t. An incumbent in period t observes its
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
sell-off value φt and makes exit and investment decisions. If the sell-off value (or the exit value)
φt exceeds the value of continuing in the industry, then the firm chooses to exit, in which case it
earns the sell-off value and then ceases operations permanently. If it decides to stay and invest,
it faces fixed costs of supplying each market, which are fX > 0 for foreign market and fD > 0
for domestic market. These market specific fixed costs capture among other things the costs of
building distribution networks. In addition, we assume that the incumbent must pay the fixed
costs of supplying each product to a market, which are fx > 0 for foreign market and fd > 0
for domestic market. These product and market-specific fixed costs capture the costs of market
research, advertising, and conforming to foreign regulatory standards for each product. As more
products are supplied to a market, total fixed costs rise, but average fixed costs fall. The firm can
invest to improve its productivity for next period. A detailed modelling of the investment decision
is given under the Investment subsection.
In addition to fixed costs, there is also a constant marginal cost for each product that depends
on firm productivity, such that qk(ϕ, λk)/ϕ units of labor are required to produce qk(ϕ, λk) units
of output of product k. Finally, we allow for variable costs of trade, such as transportation costs,
which take the standard iceberg cost form, where a fraction τ > 1 of a variety must be shipped
in order for one unit to arrive in a foreign country. We assume for simplicity that the fixed costs
of serving each market are incurred in terms of labor in the country of production, although it is
straightforward to instead consider the case where they are incurred in the market supplied.
1.1.3. Firm-Product Profitability
Demand for a product variety depends on the own-variety price, the price index for the product
and the price indices for all other products. If a firm is active in a product market, it manufactures
one of a continuum of varieties and so is unable to influence the price index for the product. At
the same time, the price of firm’s variety in one product market only influences the demand for
its varieties in other product markets through the price indices. Therefore, the firm’s inability to
influence the price indices implies that its profit maximization problem reduces to choosing the
price of each product variety separately to maximize the profits derived from that product variety.
This optimization problem yields the standard result that the equilibrium price of a product variety
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
is a constant mark-up over marginal cost:
pd(ϕ, λd) =1
ρϕ, px(ϕ, λx) = τ
1
ρϕ, (4)
where equilibrium prices in the export market are a constant multiple of those in the domestic
market due to the trade costs; λd varies across products and λx varies across products and export
markets. We choose wage in one country as the numeraire, which together with country symmetry
implies w = 1 for all countries.
Demand for a variety is:
qd(ϕ, λd) = Qkλσ−1d
[pd(ϕ, λd)
P
]−σ, qx(ϕ, λx) = Qkλ
σ−1x
[px(ϕ, λx)
P
]−σ. (5)
Substituting for the pricing rule equation (4), the equilibrium revenue in each domestic and export
market are respectively:
rd(ϕ, λd) = E(ρPϕλd)σ−1, rx(ϕ, λx) = τ1−σ
(λxλd
)σ−1
rd(ϕ, λd), (6)
where E denotes aggregate expenditure on a product and P denotes the price index for a product
(subscript product k is suppressed here). The equilibrium profits from a product in each domestic
and export market are therefore:
πd(ϕ, λd) =rd(ϕ, λd)
σ− θd, πx(ϕ, λx) =
rx(ϕ, λx)
σ− θx. (7)
Firm productivity and consumer tastes enter the equilibrium revenue and profit functions in the
same way, because prices are a constant mark-up over marginal costs and demand exhibits a
constant elasticity of substitution.
Relative revenue from two varieties of the same product within a given market depends solely
on relative productivity and consumer tastes:
r(ϕ′, λ′) =
(ϕ′
ϕ
)σ−1(λ′λ
)σ−1
r(ϕ, λ). (8)
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Similarly, as countries are symmetric, equation (7) implies that the relative revenue derived from
two varieties of the same product with the same values of productivity and consumer tastes in the
export and domestic markets depends solely on variable trade costs: rx(ϕ, λ)/rd(ϕ, λ) = τ1−σ.
A firm with a given productivity ϕ and consumer taste draw λ decides whether or not to supply
a product to a market based on a comparison of revenue and fixed costs for the product. For each
firm productivity ϕ, there is a zero-profit cutoff for consumer tastes for the domestic market, λ∗d (ϕ),
such that a firm supplies the product domestically if it draws a value of λd equal to or greater than
λ∗d (ϕ). This value of λ∗d (ϕ) is defined by:
rd(ϕ, λ∗d (ϕ)) = σθd. (9)
Similarly for the export market, λ∗x (ϕ) is given by:
rx(ϕ, λ∗x (ϕ)) = σθx. (10)
We can write λ∗d (ϕ) and λ∗x (ϕ) as function of their lowest productivity supplier, λ∗j (ϕj) for
j ∈ d, x, respectively:
λ∗j (ϕ) =
(ϕ∗jϕ
)λ∗j(ϕ∗j)
j ∈ d, x (11)
where ϕ∗j for j ∈ d, x is the lowest productivity at which a firm supplies the domestic and
the export market, respectively. As a firm’s own productivity increases, its zero-profit cutoff for
consumer tastes falls because higher productivity ensures that sufficient revenue to cover product
fixed costs is generated at a lower value of consumer tastes. In contrast, an increase in the lowest
productivity at which a firm supplies the domestic market, ϕ∗j , or an increase in the zero-profit
consumer tastes cutoff for the lowest productivity supplier λ∗j
(ϕ∗j
), raises a firm’s own zero-profit
consumer tastes cutoff. The reason is that an increase in either ϕ∗j or λ∗j
(ϕ∗j
)enhances the
attractiveness of rival firms’ products, which intensifies product market competition, and hence
increases the value for consumer tastes at which sufficient revenue is generated to cover product
fixed costs. Given τσ−1(θx/θd) > 1, a firm is more likely to supply a product domestically than to
export the product.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
1.1.4. Firm Profitability
Having examined equilibrium revenue and profits from each product, we now turn to the firm’s
equilibrium revenue and profits across the continuum of products as a whole. As consumer tastes
are independently distributed across the unit continuum of symmetric products, the law of large
numbers implies that the fraction of products supplied to the domestic market by a firm with
a given productivity ϕ equals the probability of drawing a consumer taste above λ∗d(ϕ), that is
[1 − Z(λ∗d (ϕ))]. As demand shocks are also independently and identically distributed across the
continuum of countries, the law of large numbers implies that the fraction of foreign countries to
which a given product is exported equals [1−Z(λ∗x (ϕ))]. A firm’s expected revenue across the unit
continuum of products equals its expected revenue for each product. Expected revenue for each
product is a function of firm productivity ϕ and equals the probability of drawing a consumer taste
above the cutoff times expected revenue conditional on supplying the product. Therefore total firm
revenue across the unit continuum of products in the domestic and export markets is:
rj(ϕ) =
∫ ∞λ∗j (ϕ)
rj(ϕ, λj)z(λj)dλj j ∈ d, x . (12)
total profits for domestic and export market is:
πj(ϕ) =
∫ ∞λ∗j (ϕ)
[rj(ϕ, λj)
σ− fj
]z(λj)dλj − Fj j ∈ d, x (13)
Total profit is:
π(ϕ) = πd(ϕ) + πx(ϕ). (14)
Equilibrium revenue from each product within the domestic market, rj(ϕ, λj), is increasing
in firm productivity and consumer tastes. Hence the lower a firm’s productivity, ϕ, the higher its
zero-profit consumer tastes cutoff, λ∗d (ϕ), and the lower its probability of drawing a consumer tastes
high enough for a product to be profitable. Therefore firms with lower productivities have lower
expected profits from individual products and supply a smaller fraction of products to the domestic
market, [1−Z(λ∗d (ϕ))]. For sufficiently low firm productivity, the excess of domestic market revenue
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
over product fixed costs in the small range of profitable products falls short of the fixed cost of
supplying the domestic market, Fd. The same is true for export market.
The profit function satisfies the following properties:
1. Total profit for domestic and export market is increasing in ϕ.
2. For all ϕ ∈ R+ and t, π(ϕ) > 0 and supϕπ(ϕ) <∞.
3. lnπ(ϕ) is continuously differentiable.
4. Strengthened competition cannot result in increased profit due to competition for labor.
The increased labor demand by the more productive firms and new entrants bids up the real wages
and forces the least productive firms to exit. Work by Bernard and Jensen (1999) suggests that this
channel substantially contributes to U.S. productivity increases within manufacturing industries.
1.1.5. Aggregation and Market Clearing
An equilibrium will be characterized by a mass M of firms and a distribution g(ϕ) of productivity
levels over a subset of [0,∞). The weighted average productivity in the domestic and export market,
respectively, is:
ϕj =
[∫ ∞0
(ϕλj(ϕ)
)σ−1g(ϕ)dϕ
] 1σ−1
, j ∈ d, x , (15)
where λd(ϕ) denotes weighted-average consumer tastes in the domestic market for a firm with
productivity ϕ:
λj(ϕ) =
[∫ ∞0
(λj(ϕ))σ−1 z(λj)dλj
] 1σ−1
j ∈ d, x . (16)
The aggregate price index P is then given by:
P =
[Md
∫ ∞0
pd (ϕ)1−σ g(ϕ)dϕ+ nMx
∫ ∞0
px (ϕ)1−σ g(ϕ)dϕ
] 11−σ
=
[Md
(1
ρϕd
)1−σ+ nMx
(1
ρϕx
)1−σ] 1
1−σ
. (17)
The weighted average productivity of all firms (domestic and foreign) competing in a single
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
country is:
ϕ =
1
M
[Mdϕ
1−σd + nMx
(τ−1ϕx
)1−σ] 11−σ
. (18)
where the productivity of exporters is adjusted by the trade cost τ. Thus the aggregate price index
P and revenue R can be written as functions of only the productivity average ϕ and M :
P = M1
1−σ1
ρϕR = Mrd(ϕ). (19)
1.2. Dynamic Model
In this section we formulate the static model discussed in the previous section into a dynamic model.
The model evolves over discrete time periods and an infinite horizon. We index time periods with
non-negative integers t ∈ N (N = 0, 1, 2, ...) .
Firm heterogeneity is reflected through firm states. We refer to a firm’s state as its productivity
level. At time t, the productivity level of firm i is ϕit ∈ R+.We define the industry state st to be
the number of incumbent firms Mt and the average productivity ϕt in period t. We define the state
space S = s ∈ R2+|M ∗ ϕ <∞In each period, each incumbent firm earns profits. As in the static
model, a firm’s single period profit πt(ϕt, st) depends on its productivity ϕt and the aggregate price
index Pt, which can be written as a function of the productivity average ϕt and mass of firms Mt
in period t.
The model also allows for entry and exit. In each period, each incumbent firm observes a
positive real-valued sell-off value φit that is private information to the firm. If the sell-off value
exceeds the value of continuing in the industry, then the firm may choose to exit, in which case it
earns the sell-off value and then ceases operations permanently.
In each period potential entrants can enter the industry by paying a fixed entry cost fEN .
Entrants do not earn profits in the period that they enter. They appear in the following period
with productivity and consumer tastes drawn from g(ϕ) and z(λ) and can earn profits thereafter.
Each firm aims to maximize expected net present value. The interest rate is assumed to be positive
and constant over time, resulting in a constant discount factor of β ∈ (0, 1) per time period.
In each period, events occur in the following order:
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
1. Each incumbent firm observes its sell-off value φit, productivity at t+1, and demand shocks.
2. The number of entering firms is determined and each entrant pays an entry cost of fEN .
3. Incumbent firms choose price and quantity to maximize profit.
4. Incumbent firms choose investment, exporting, and number of products to maximize the
expected net present values.
4. Exiting firms exit and receive their sell-off values.
5. Productivity in t+ 1 is realized and new entrants enter.
We assume that there are an asymptotically large number of potential entrants who play
a symmetric mixed entry strategy. This results in a Poisson-distributed number of entrants (see
Weintraub, Benkard, and Van Roy (2008b) for a derivation of this result). Our associated modeling
assumptions are as follows:
Assumption:
1. The number of firms entering during period t is a Poisson random variable that is
conditionally independent of ϕit, λit,εit|t > 0, conditioned on st.
2. fEN < βφ, where φ is the expected net present value of entering the market, investing
zero and earning zero profits each period, and then exiting at an optimal stopping time.
We denote the expected number of firms entering in period t, by MEN,t. This state-dependent
entry rate will be endogenously determined, and our solution concept will require that it satisfies a
zero expected discounted profits condition. Modeling the number of entrants as a Poisson random
variable has the advantage that it leads to simpler dynamics. However, other entry processes can
be used as well. Assumption 2 ensures that the sell-off value by itself is not sufficient reason to
enter the industry.
1.2.1. Evolution of Productivity
In order to model the firm’s dynamic optimization problem for exporting, investment, and product
restructuring decisions we begin with a description of the evolution of the process for firm produc-
tivity ϕit. We assume that productivity evolves over time as a Markov process that depends on
firm’s investment, its participation in the export market, the number of products firm produces,
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and a random shock:
ϕit = z(ϕit−1, Iit−1, Xit−1,Nit−1) + ξit (20)
Iit−1, Xit−1, Nit−1 are, respectively, the firm’s investment, export market participation, and num-
ber of products produced in the previous period. Note that this specification is very general as
the function z may take on either positive or negative values (e.g., allowing for positive depreci-
ation).The inclusion of Iit−1 recognizes that the firm may affect the evolution of its productivity
by investing. The inclusion of Xit−1 allows for the possibility of learning-by-exporting, that par-
ticipation in the export market is a source of knowledge and expertise that can improve future
productivity. The inclusion of Nit−1 allows for the possibility of learning-by-doing, that producing
more products exposes the firm to a bigger pool of knowledge that can improve its future produc-
tivity. In the empirical section, we assess the strength of each of these decisions. The stochastic
nature of productivity improvement is captured by ξit which is treated as an iid shock with zero
mean and variance σ2ξ . This stochastic component represents the role that randomness plays in the
evolution of a firm’s productivity. Uncertainty may arise, for example, due to the risk associated
with a research and development endeavor or a marketing campaign.
We also assume there exists a positive constant z ∈ R+ s.t. |z(I,X,N, ε)| ≤ z, for all
(I,X,N, ε).There exists a positive constant I, X, N s.t. Iit < I, Xit < X, Nit < N, for all
i, t. This assumption places a finite bound on how much progress can be made or lost in a single
period. Under perfect capital market, firms cannot invest more than their expected net present
value2. Xit is modeled as a discrete 0/1 variable in the empirical section. If modelled as a contin-
uous variable, export volume is bounded by the consumer demand. Similarly, Nit is also bounded
by the consumer demand.
1.2.2. Dynamic Decisions- Investment, Exporting, and Product Restructuring
In this section, we develop the firm’s dynamic decision to export, invest and the number of products
to produce. If the firm instead decides to remain in the industry, then it must choose the number
2We assume perfect capital market, firms investment decisions are constrained by the net present value of thefirm, i.e. firms cannot borrow an infinite amount to increase their productivity. The role of imperfect capital marketis left for future research.
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of products to produce, whether to export, and how much to invest to improve its productivity
level. We denote the unit cost of investment by d. We assume that the firm decides whether to
stay in operation after observing the scrap value φit, and make the number of products and export
decisions in year t after observing the fixed costs of operating in domestic market (Fd), export
market (Fx),and fixed costs for each additional product produced in domestic and export market,
(fd, fx) if it decides to remain in operation. We model these fixed costs as iid draws from a known
join distribution Gf . The firm i′s value function in year t if it chooses to continue, can be written
as:
V stay(ϕit, st) = maxXit
∫V Dλd
(ϕit, st)dGf ,
∫V Eλd
(ϕit, st)dGf
(21)
where Xit is a discrete 0/1 variable identifying the firm’s export choice in period t, V Dλd
(ϕit, st) is
the current and expected future profit from producing products in domestic market only:
V Dλd
(ϕit, st) = maxλ∗d
∫ ∞λ∗d
[rd(ϕ, λd)
σ− fd
]z(λd)dλd − Fd + V D(ϕit, st)
where V D(ϕit, st) is the value of a non-exporting firm after it makes its optimal investment decision:
V D(ϕit, st) =
∫ maxIit
βEtVit+1(ϕit, st+1|Xit = 0, Nit = [1− Z(λ∗d)] , Iit = Iit)
−dIit − 1(Iit>0)fI
dGf
where if firm chooses to invest Iit, it incurs the cost of investment dIit and a fixed cost compo-
nent of investment fI . It has an expected future return which depends on how investment affects
future productivity. Similarly V Eλd
(ϕit, st) is the current and expected future profit from producing
products in both domestic and export market:
V Xλd
(ϕit, st) = maxλ∗d
∫ ∞λ∗d
[rd(ϕ, λd)
σ− fd
]z(λd)dλd − Fd
+ maxλ∗x
∫ ∞λ∗x
[rx(ϕ, λx)
σ− fx
]z(λx)dλx − Fx + V E(ϕit, st)
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where V E(ϕit, st) is the value of an exporting firm after it makes its optimal investment decision:
V X(ϕit, st) =
∫ maxIit
βEtVit+1(ϕit, st+1|Xit = 1, Nit = [1− Z(λ∗d)] , Iit = Iit)
−dIit − 1(Iit>0)fI
dGf
This shows that the firm chooses to export in year t when the current plus expected gain in
future export profit exceeds the relevant fixed cost of exporting. Finally, to be specific, the expected
future value conditional on different choices for Xit, Nit,and Iit for firm staying in operation is:
EtVstay(ϕit+1, st+1|Xit,Nit, Iit) =
∫s′
∫ϕ′
V stay(ϕ′, s′)dF (ϕ′|Xit,Nit, Iit)dP (s′|st).
In this equation the evolution of productivity dF (ϕ′|Xit,Nit, Iit) is conditional on Xit,Nit, and
Iit because of the assumption in equation (21). In this framework, the net benefit of product
restructuring, exporting and investment are increasing in current productivity. This leads to the
usual selection effect where high productivity firms are more likely to produce more products,
export, and invest. By making future productivity endogenous this model recognizes that current
choices lead to improvements in future productivity and thus more firms will self-select into, or
remain in, multi-products, exporting and investment in the future.
After observing φit, if the firm chooses to exit, its exiting value function is current period profit
with optimized Xit(ϕit, st), Nit(ϕit, st), Iit(ϕit, st) decisions plus the scrap value of exit:
V exit(ϕit, st) =
∫[π(ϕit, st, Nit(ϕit, st), Xit(ϕit, st), Iit(ϕit, st))] + φitdG
f
where
maxIit
βπ(ϕit, st, Nit(ϕit, st), Xit(ϕit, st), Iit(ϕit, st)) =
πd(ϕit, st, Nit(ϕit, st)) + 1(Xit(ϕit,st)=1)πx(ϕit, st, Nit(ϕit, st))− dIit(ϕit, st)− 1(Iit(ϕit,st)>0)fI
Firm i stays in operation in period t if V stay(ϕit, st) > V exit(ϕit, st).
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
2. Equilibrium
As a model of industry behavior we focus on pure strategy Markov perfect equilibrium (MPE), in
the sense of Maskin and Tirole (1988). We further assume that equilibrium is symmetric, such that
all firms use a common stationary investment, export, product restructuring and exit strategy. In
particular, there is a function I,X,N such that at each time t, each incumbent firm i invests an
amount Iit = I(ϕit, st), exports amount Xit = X(ϕit, st), and produce Nit = N(ϕit, st) number of
products. Similarly, each firm follows an exit strategy that takes the form of a cutoff rule: there is
a real-valued function η such that an incumbent firm i exits at time t if and only if φit ≥ η(ϕit, st).
Weintraub, Benkard, and Van Roy (2008b) show that there always exists an optimal exit strategy
of this form even among very general classes of exit strategies. Let Γ denote the set of investment,
export, product restructuring and exit strategies such that an element µ ∈ Γ is a set of functions
µ = (I,X,N, η), where I : R+ x S− > R+ is an investment strategy, X : R+ x S− > R>0 is an
export strategy, N : R+ x S− > N is a number of products to produce strategy, and η : R+ x
S− > R+ is an exit strategy. Similarly we denote the set of entry rate functions by Ω, where an
element of Ω is a function $ : S− > R+.
We define the value function V (ϕ|µ,$) to be the expected net present value for a firm at state
(productivity) ϕ when its competitors’ state is s,given that its competitors each follows a common
strategy µ ∈ Γ, the entry rate function is $ ∈ Ω, and the firm itself follows strategy µ ∈ Γ. In
particular,
V (ϕ, s|µ,$) = Eµ,$
[Ti∑k=t
βk−t (π(ϕik, sk, µ (ϕik, sk))) + βTi−tφi,Ti |ϕit = ϕ, st = s
], (22)
where Ti is a random variable representing the time at which firm i exits the industry, and the
subscripts of the expectation indicate the strategy followed by firm i and its competitors, and the
entry rate function.
An equilibrium to our model consists of an investment, export, product restructuring, and
exit strategy µ = (I,X,N, η) ∈ Γ,and an entry rate function $ ∈ Ω that satisfy the following
conditions:
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1. Incumbent firm strategies represent a MPE:
supµ′V (ϕ, s|µ′, µ,$) = V (ϕ, s|µ,$) ∀ϕ ∈ R+, ∀s ∈ S. (23)
2. At each state, either the entrants have zero expected discounted profits or the entry
rate is zero (or both):
∑s∈S $(s) (βEµ [V (ϕ, st+1|µ,$)|st = s]− fEN ) = 0
βEµ,$ [V (ϕ, st+1|µ,$)|st = s]− fEN ≤ 0 ∀s ∈ S
$(s) ≥ 0 ∀s ∈ S.
And the labor market clears in each period. Weintraub, Benkard, and Van Roy (2008b) showed
that the supremum in part 1 of the definition above can always be attained simultaneously for all
ϕ and s by a common strategy µ′.
Doraszelski and Satterthwaite (2007) establish existence of an equilibrium in pure strategies
for a closely related model. We do not provide an existence proof here because it is long and
cumbersome and would replicate this previous work. With respect to uniqueness, in general we
presume that our model may have multiple equilibria.3
Dynamic programming algorithms can be used to optimize firm strategies and equilibria to
our model can be computed via their iterative application without the curse of dimensionality
problem commonly seen in the IO literature because st can be completely characterized by ϕt.
Stationary points of such iterations are MPE. An algorithm for computing the MPE is included
under Empirical Analysis section.
2.0.3. Market Clearing:
The feasibility constraint on the investment and entry is: MEN,tfEN = LEN,t, Mt(dIt) = LI,t.Total
payments to labor used in entry are equal to expected discounted profits LEN,t = Mtvt, where
vt =∫V (ϕ, st)Mt(st)g(ϕ)dϕ. The evolution of the distribution of operating firms Mt over time
is given by the optimal strategy µ consisting of I,X,N, η and entry rate $. Total payments to
labor used in production and investment, on the other hand, are equal to revenue minus expected
3Doraszelski and Satterthwaite (2007) also provide an example of multiple equilibria in their closely related model.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
discounted profits, Lp,t+LI,t = R−Mtvt Combining these two expressions, L = R. Thus the labor
market clears: LEN,t + LI,t + Lp,t = L.
3. Empirical Analysis
We begin with a description of the evolution of the process for firm productivity ϕit. We assume
that productivity in period t evolves over time as a Markov process that depends on the firm’s
investments Iit−1 in period t-1, its participation in the export market Xit−1 in period t-1, the
number of products firm produces Nit−1 in t− 1 and a random shock:
lnϕit = α0 + α1 lnϕit−1 + α2 lnϕ2it−1 + α3 lnϕ3
it−1
+α4 ln Iit−1 + α5Xit−1 + α6Nit−1 + ξit. (24)
Here we model investment as a continuous choice to allow for the possibility that firms can increase
their productivity faster by investing more. The inclusion of Xit−1 recognizes that the firm may
affect the evolution of its productivity through learning-by-exporting. The inclusion of Nit−1 allows
the possibility of expanding into multiple products to have an effect on productivity. The stochastic
nature of productivity improvement is captured by ξit which is treated as an iid shock with zero
mean and variance σ2ξ . This stochastic component represents the role that randomness plays in the
evolution of a firm’s productivity. This is the change in the productivity process betweent−1 and t
that is not anticipated by the firm and by construction is not correlated with ϕit−1, Iit−1, Xit−1,and
Nit−1.This allows the stochastic shocks in period t to be carried forward into productivity in future
years.
3.1. Algorithm
To compute the MPE with the two-step-PML method, the beliefs about transition, entry, invest-
ment, export and exit strategies are computed non-parametrically. The second step is to construct
a likelihood function using those beliefs and estimate the structural parameters of interest. When
consistent nonparametric estimates of choice probabilities either are not available or are very im-
precise, we can use k-step-PML or NPL algorithm to compute the MPE. NPL works as follows,
start with any set of beliefs/strategies and compute the structural parameters of interest, update
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
strategies with the estimated structural parameters non-parametrically, then construct likelihood
function and update the structural parameters. Repeat this k times until the strategies converge.
3.1.1. Demand and Cost Parameters
We begin by estimating the domestic demand, marginal cost and productivity evolution pararme-
ters. The domestic revenue function for a single product firm in log form with an iid error term uit
that reflects measurement error in revenue or optimization errors in price choice is:
ln rd,it = (σd − 1) ln
(σd − 1
σd
)+ (σd − 1) lnϕit
+ lnEt + (σd − 1) lnPt + (σd − 1)λit + uit (25)
where λit is the unobserved demand shock for firm i in domestic market in time t. The composite
error term (σ − 1) ln (ϕit) + uit contains firm productivity. Since the inputs are observed at firm
level, using the product-level information requires an extra step of aggregating the data at the
product level to the firm level. From equation (25) I can aggregate the production function to the
firm level by assuming identical production functions across products produced which is a standard
assumption in empirical work, see for instanceBernard and Jensen (2008) and De Loecker (2010).
Under this assumption, and given that I observe the number of products each firm produces, I can
relate the average production of a given product k of firm Qikt to its total input use and the number
of products produced. The production function for product k of firm i is then given by:
Qikt = N−1it Qit (26)
where N is the number of products produced. Introducing multi-product firms in this framework
explicitly requires to control for the number of products product. Combining the production
function and the expression for price from equation (4) leads to an expression for total revenue
as a function of inputs, productivity, and the number of products.
ln rd,it = lnNit + (σd − 1) ln
(σd − 1
σd
)+ (σd − 1) lnϕit
+ lnEt + (σd − 1) lnPt + (σd − 1) lnλit + uit (27)
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where λit is the average unobserved demand shock across all products for firm i in time t and N
is the number of products produced. For a single product firm, ln(1) = 0, and therefore this extra
term cancels out, whereas for multi-product firms an additional term is introduced.
We estimate firm productivity using Olley and Pakes (1996) and Levinsohn and Petrin (2003)
approach to rewrite the unobserved productivity in terms of expenditure on intermediate goods
for each firm. In general, the firm’s choice of the variable input levels for materials, mit, and
electricity, eit, will depend on the level of productivity and the demand shocks (which are both
observable to the firm). Under our model setting, marginal cost is constant in output, the relative
expenditures on all the variable inputs will not be a function of total output and thus not depend
on the demand shocks. In addition, differences in productivity will lead to variation across firms
and time in the mix of variable inputs used. Thus, material and energy expenditures by the firm
will contain information on productivity level. We can write the level of productivity, conditional
on the number of products produced, as a function of the variable input levels:
ϕit = ϕit(Nit,mit, eit) (28)
We can rewrite (27) as follows:
ln rd,it = γ0 +T∑t=1
M∑m=1
γmtDmDt + h(Nit,mit, eit) + vit (29)
where intercept γ0 is the demand elasticity terms, Dt is the time varying aggregate demand shock,
Dm is the market-level factor prices,mit is expenditure on intermediate goods, and h(.) captures
the effect of productivity on domestic revenue. We specify h(.) as a cubic function of its arguments
and estimate (28) with OLS. The fitted value of the h (.) function, which we denote hit is an
estimate of lnNit+ (σ − 1) lnϕit. Next, we can construct an estimate of productivity for each firm.
Substituting lnϕit = (h− lnNit)/ (σ − 1) into productivity evolution equation (24):
hit − lnNit = α∗0 + α1(hit−1 − lnNit−1) + α2(hit−1 − lnNit−1)2 + α3(hit−1 − lnNit−1)3
+α∗4 ln Iit−1 + α∗5Xit−1 + α∗6Nit−1 + ξ∗it. (30)
where the star represents that the α coefficients are multiplied by (σd − 1) . This equation can be
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
estimated with nonlinear least squares and the underlying parameters α can be retrieved with an
estimate of demand elasticities σd. We can estimate the demand elasticities using data on total
variable cost. Total variable cost is an elasticity-weighted combination of total revenue in each
market:
tvcit = ρd ∗ rd,it + ρx ∗ rx,it + εit (31)
where ρj = 1 − 1/σj for j = d, x. Finally given estimate of σd, we can construct an estimate of
productivity for each observation as:
ln ϕit = (h− lnNit)/ (σd − 1) . (32)
Three aspects of this static empirical model are worth mentioning. First, because firm hetero-
geneity plays a crucial role in both the domestic and export market, we utilize data on firm revenue
to estimate firm productivity. Second, we’ve also used total variable costs to estimate demand
elasticities in both export and domestic market. Third, estimation of the process for productivity
evolution is important for firm’s dynamic investment equations because the parameters from equa-
tion (30) are used directly to construct the value functions that underlie firm’s investment, export,
and number of products choice.
The Melitz (2003) framework assumes the only factor of production is labor. For a Cobb-
Douglas technology, the domestic revenue function becomes:
ln rd,it = lnNit + (σd − 1) ln
(σd − 1
σd
)+ (σd − 1) (β0 − βk ln kit − βω lnωt + lnϕit)
+ lnEt + (σd − 1) lnPt + (σd − 1) lnλit + uit (33)
where kit is firm’s capital stock and ωt is a vector of variable input prices common to all firms.
Productivity, conditional on the number of products produced and capital stock, can be written as
a function of the variable input levels: ϕit = ϕit(Nit,mit, eit). Equation (29) becomes :
ln rd,it = γ0 +
T∑t=1
M∑m=1
γmtDmDt + h(Nit, kit,mit, eit) + vit (34)
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The fitted value of the h(.) function, denoted hit, is an estimate of lnNit+(σ − 1) (−βk ln kit+lnϕit).
Next, we can construct an estimate of productivity for each firm by substituting lnϕit = (h −
lnNit)/ (σ − 1) + βk ln kit into productivity evolution equation (24). The productivity evolution
equation can be estimated with nonlinear least squares and the underlying βk parameter can be
retrieved given an estimate of σd. Finally, given estimates of βk and σd, we can construct an
estimate of productivity for each firm as:
ln ϕit = (h− lnNit)/ (σd − 1) + βk ln kit. (35)
3.1.2. Dynamic Parameters
The algorithm below is designed to compute the beliefs about transition, entry, investment, export,
exit strategies and the value function associated with these strategies with a positive entry rate
given some values of structural parameters. It starts with two extreme entry rates: $ = 0 and
$ =1
fEN
(supϕ,s π(ϕ, s)
1− β+ φ
). Any equilibrium entry rate must lie in between these two extremes.
The algorithm searches over entry rates between these two extremes for one that leads to the
MPE strategies and the value function associated with these strategies given a set of structural
parameters. For each candidate entry rate, an inner loop (step6-10) computes an MPE firm strategy
for that fixed entry rate. Strategies are updated smoothly (step 9).4 If the termination condition
is satisfied with ε1 = ε2 = 0, we have a set of MPE beliefs given structural parameters.
The algorithm is easy to program and computationally efficient. In each iteration of the inner
loop, the optimization problem to be solved is a one dimensional dynamic program. The state space
in this dynamic program is the set of productivity levels a firm can achieve. In principle, there
could be an infinite number of them. However, beyond a certain productivity level the optimal
strategy for a firm is not to invest, so its quality cannot increase to beyond that level.
4The parameters γand N were set after some experimentation to speed up convergence.
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4. Data
4.1. Spanish Firm Level Data
The model developed in the last section will be used to analyze the sources of productivity change
of firms in Spain. The micro data used in estimation was collected by SEPI Foundation in Spain for
the years 1999-2008. The products are classified into 20 manufacturing industries based on 3-figure
CNAE-93 codes.
The data set we use is a collection of 3216 firms that operated in at least one of the five years
between 1999–2008 and that reported necessary data on domestic and export revenue, investment,
total variable costs, and number of products they are producing. Only 848 of those firms operated
in all tenS years between 1999-2008.
Table 1 provides the summary measures of the size of the firms, measured in revenues and
average employment. The top panel of the table provides the median firm size across operating
firms in our sample in each year, while the bottom panel summarizes the average firm size. The
first column shows that approximately 35 percent of the firms that do not export in a given year.
The median firm’s domestic revenue varies from 14.34 to 17.46 in hundred of thousands of Euros.
Among the exporting firms, the median firm’s domestic revenue is approximately eight times as
large, 10.5 to 12.9 million Euros. The export revenue of the median firm ranges from 3.4 to 5.5
million Euros. The median number of products for both exporters and non-exporters are 1, while
the average number of products produced by non-exporters ranges from 1.07 to 1.14 and the 1.13
to 1.15 for exporters.
The distribution of the firm revenue is highly skewed, particularly for firms that participate in
the export market. The average domestic firm revenues are larger than the medians by a factor of
approximately six for the exporting firms and the average export revenues are larger by a factor of
approximately 10. The skewness in the revenue distributions can also be seen from the fact that
the 100 largest firms in our sample in each year account for approximately 40 percent of the total
domestic revenue and 75 percent of the export revenue. The skewness in revenues will lead to large
differences in profits across firms and a heavy tail in the profit distribution. To fit the participation
patterns of all the firms it is necessary to allow the possibility that a firm has large fixed and/or
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sunk costs. We allow for this in our empirical model by assuming exponential distributions for the
fixed and sunk costs. Together this assumption allows for substantial heterogeneity in the costs
across plants.
The other important variable in the data is the number of products the firms choose to produce.
Number of products in the sample is defined as the number of products at 3 figures CNAE-93 each
firm produces. Even though in the sample only five percent of the firms produce more than 1
product, they account for 20 percent of the total domestic revenue and 25 percent of the export
revenue.
The last important variable in the data is the investment the firms make each year. Table 2
provides summary statistics for different measures of investment for exporters and non-exporters.
We look at two measures of investment. The first one is investment on capital goods which includes
the purchases of information processing equipment, technical facilities, machinery and tools, rolling
stock and furniture, office equipment and other tangible fixed assets. The second one is total
expenses on R&D which is the sum of the salaries of R&D personnel (researchers and scientists),
material purchases for R&D, and R&D capital (equipment and buildings) expenses. The first
column in Table 2 provides the percentage of firms with positive investment in capital in each year.
In our sample, approximately 70 percent of the non-exporters invest in capital where close to 90
percent of the exporters invest in capital. Only 10 percent of non-exporters induce R&D expenses,
whereas 50 percent of the exporters induce R&D expenses. The top panel of the second column
provides the median of the capital investment given positive investment from operating firms, and
the bottom panel provides the mean of the capital investment given positive investment. The
average positive investment in capital is approximately ten times as large as the median positive
capital investment for non-exporters and six times for exporters. All numbers in the table are
expressed in tens of thousands of Euros. Median investment in capital for non-exporters ranges
from 40 to 50 thousand Euros and 500-700 thousand Euros for exporters. Average investment in
capital for exporters is approximately seven times that of the non-exporters. The average positive
R&D expenses are approximately 5 times the median positive R&D expenses for non-exporters,
and ten times of that for exporters. The difference in mean and median of the R&D expenses
between non-exporters and exporters is also approximately ten folds.
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4.2. Empirical Transition Patterns for Entry/Exit, Investment, and Export
In this section we summarize the patterns of entry, exit, R&D and exporting behavior in the sample,
with a focus on the transition patterns that are important to estimating the fixed and sunk costs
of entry, R&D, and exporting. Table 3 reports entry and exit rates over the years for firms that
operated at least one year during 1999-2008. Operating firms are defined as firms with positive
revenue. The first column reports the number of firms with positive revenue in each year. The
second column reports the number of non-operating firms in the sample. Column 3 and 4 report
the number of new entrants and exits in each year. New entrants are defined as firms generated
positive revenue in time period t and zero revenue in time period t-1. Similarly for exits, firms that
generated revenue in period t-1 but stopped operating in period t are defined as exits. In the year
2003, there are no new entrants and a high exit rate of 19 percent. This is the year following the
technology bubble and 911 . Year 2004 has no entry and close to zero exits. In the year 2005, entry
rate shot up to 33 percent with 7 percent of exit rate and in the year 2006 entry rate falls back to
15% and exit rate goes up to 10%. The average entry and exit rate for this time period is 14 and 9
percent. With significant entry and exit behaviors present, ignoring firms self selection into entry
and exit will result in biased estimates of investment and export decisions.
Table 4 reports the proportion of firms that undertake each combination of the activities and
the transition rates between pairs of activities over time. The top panel of Table 4 reports the
average proportion of operating firms in both period t and t+1 that undertake neither investment
nor export, investment only, export only, and both investment and export and the transition rates
between pairs of activities over time. The middle panel reports those for new entrants in period t
that continue to operate in t+1. The bottom panel reports those for firms that cease to produce
in t+2, but operate in both t+1 and t. The first row of each panel reports the cross-sectional
distribution of exporting and investment averaged over all years. It shows that in each year, the
proportion of operating firms undertaking neither of these activities is .11. This number is higher
for new entrants and firms that will cease to produce. The proportion that invest but do not export
is .25 for operating firms. This number is higher for new entrants and lower for firms that will cease
production in the sample, suggesting that new entrants are more likely to invest to improve their
productivity due to a bad luck in the productivity draw and firms that have a higher probability of
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exit are the ones with lower productivity and therefore don’t bother to invest. The proportion that
export only and do not invest .07 for operating firms, .08 for new entrants and .11 for firms that
will exit. The proportion that do both for operating firms is .57, which is higher than the number
for new entrants and firms that will exit. Overall, 82% of the operating firms engage in investments
and 64% of the operating firms export5. One explanation for difference in export and investment
participation is that differences in productivity and the export demand shocks affect the return of
each activity and the firms self-select into each activity based on the underlying profits.
The transition patterns among investment and exporting are important for the model estima-
tion. The last four rows in each panel of the table report the transition rate from each activity in
year t to each activity in year t+1. Several patterns are clear. First, there is significant persistence
in the status over time for all three panels. This can reflect a high degree of persistence in the
underlying sources of profit heterogeneity, which in our model, is productivity and the export mar-
ket shocks. Of the operating firms that did neither activity in year t, .67 of them are in the same
category in year t+1. This number is .88 for firms that will exit and only .49 for new entrants.
This suggests that even though there is persistence in the status over time, different kind of firms
will have different level of persistence. New entrants that did not invest nor export are more likely
to invest than the incumbent firms and firms that will exit soon will be less likely to invest than
the incumbent firms. The probability of remaining in the same category over adjacent years is .79,
.49, and .92 for invest only, export only, and both for operating firms. These numbers are similar
for new entrants and firms that will soon exit except for invest only. Firms that will soon exit with
positive investment in period t are less likely to invest in t+1 when they decide to exit at the end
of period t+1. This differences in persistence reflect the importance of modeling firms self-selection
into entry and exit.
Second, firms that undertake one of the activities in year t are more likely to start the other
activity than a firm that does neither. This is true for all firms. If the firm does neither activity in
year t, it has a probability of .03 to enter the export market and .31 to invest in the next period for
operating firms. These number are .07 and .85 for firms that only invest in period t, .93 and .47 for
firms that only export in period t, and .98 and .94 for firms that do both in period t. Third, firms
5The export participation rate in Spain is comparable to those firms in France. The export participation rate ofFrench firms (with 20 employees or above) is 69.4% in 1990 and 74.8% in 2004.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
that conduct both activities in year t are less likely to abandon one of the activities than firms that
only conduct one of them. Operating firms that conduct both activities have a .06 probability of
abandoning investment and a .02 probability of leaving the export market. Operating firms that
only do investment have a .15 probability of stopping in investment while firms that only export
have a .07 probability of stopping in export. Exiting firms that only do investment have a .44
probability of stopping and those who only do export have a .03 probability of stopping. Fourth,
export only firms are much more likely to do both (.44 probability) than investment only firms
(only .06 probability).
The transition patterns reported in Table 4 illustrate the need to model the investment and
exporting decision jointly. In our model, firms cannot export below a certain productivity cut-
off. Therefore firms need to invest and increase their productivity in order to export. The return
to investment can be higher or lower for exporting versus non-exporting firms, which makes the
probability that the firm will choose to invest dependent on the firm’s export status. Table 5
illustrates the average productivity constructed from equation 30 in each year for operating firms,
new entrants, firms that exit, and firms that operated in all 5 years.
5. Results
5.1. Demand, Cost and Productivity Evolution
The parameter estimates from the first stage estimation of equations 31 and 32 are reported in
Table 6. The first column reports the estimates using investment in capital, which we also use in
the dynamic model. The second column reports estimates using investment in R&D.
Focusing on the first column, the implied value of the demand elasticity for domestic and
export markets are 7.55 and 2.11. These elasticity estimates imply markups of price over marginal
cost of 15.3 percent for domestic market sales and 89.7 percent for foreign sales. The coefficient
on α1 measures the effect of the lagged productivity on current productivity and it is positive and
significant. The coefficient α4 measures the effect of investment on capital on current productivity.
Firms that increase their investment by 1% can increase their productivity by .03%. The effect of
past exporting on current productivity is given by α5. This a measure of learning-by-exporting’s
impact on productivity and in this case is not significant suggesting very little learning-exporting.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
The last coefficient α6 measures the impact of product restructuring on productivity. Producing
one more product increases firm’s productivity by 6%. This suggests learning by diversifying.6
Relative to a firm that never invests nor exports, a firm that invests an amount equal to the
average investment in capital goods and export will have mean productivity that is 111% higher. A
firm that does not export but able to invest the average investment is 104% higher in productivity.
A firm that only exports is 8% higher in productivity. A firm that produces one additional product
is 4.1% lower. While this provides a summary of the technology linkages between exporting,
investing, diversifying, and productivity, it does not recognize the impact of this process on the
firm’s choice to enter into operation and exporting. This behavioral response is the focus of the
second stage estimation. Given the estimates in Table 6 we construct estimate of firm productivity
from equation 30. The mean of the productivity estimates is 2.36 among operating firms and
the (.05, .95) percentiles of the distribution are (1.97, 2.78). The mean of productivity estimates
including the 0’s is 1.47 with (.05, .95) percentiles of the distribution (0, 2.7). The variation in
productivity will be important in explaining which firms self-select into entry/exit, exporting and
diversifying.
We can assess how well the productivity measure correlates with the firm’s entry/exit, export
and product restructuring choices. In the top panel of Table 7 we report estimates of a probit
regression of exporting on the firm’s productivity, lagged investment on capital goods, lagged
export dummy, lagged number of products, and a set of time, industry, and time cross industry
dummies. This regression is similar to the reduced form policy functions that come from our
dynamic model. The export demand shocks are not included explicitly but rather captured in the
error terms. In the probit model, all the coefficients are highly significant. Both productivity and
lagged export status play a positive and significant role in determining the current export status.
The coefficients on investment and product restructuring are negative and significant, suggesting
crowding out effect from investment and product restructuring. In the second and third row of the
top panel we report OLS regressions of export revenue for firms in the export market in equation
(). The explanatory variables are productivity and a set of dummies (industry, time, and industry
6The second column repeats the estimation using log of R&D expenditure rather than log of investment on capitalgoods. This does not change any sign nor significance of the coefficients in the model.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
cross time effects). The lagged export dummy and investment choice do not affect the volume once
the firm is in the export market. Since the Spanish firm data does not provide information on how
many products firms export, the number of products choice is also not included. The R square
term for the regression without fixed effects is .66 and .69 for the regression without fixed effects,
suggesting export demand heterogeneity is not a source of size and profit differences in the export
market. (more on this)
The first row of the second panel in Table 7 reports estimates of a probit regression of firm
exit. Firm is defined as exit in period t if it has zero total revenue (domestic plus export) in the
period t+1. This definition of firm exit is consistent with the way we model firm entry/exit where
we assumed in each period firms make their production decisions, produce, and decide if they want
to exit and receive a scrap value at the end of the period. Firms with higher productivity are less
likely to exit the market. This is both economically and statistically significant. The parameter on
investment is insignificant. Multi-product firms are less likely to exit the market. Being an exporter
in the past makes the firm more likely to exit. One explanation for this is firms involved in the
export market are more likely to respond to the negative demand shocks in the export market.
(more on this, maybe do an exit to export market from existing exporting firms).
The last panel in Table 6 reports estimates of an OLS regression of firm’s product restructuring
choice.7 The dependent variable is the number of products firm chooses to produce. Firms with
higher productivity will produce more products.(more on this)
Overall, it is clear from these reduced form regressions that the productivity variable we have
constructed is measuring an important plant characteristic that is correlated with export and
entry/exit decisions and the firm’s export and domestic revenue once they choose to participate in
the market. We report the estimates of the dynamic investment equations in the next section.
5.2. Dynamic Estimates
The remaining cost, export demand parameters, entry and exit rates are estimated in the second
stage of the empirical model using the likelihood function that is the product over the firm-specific
joint probability of the data given in equation (). The coefficients reported in Table 8 are the means
and standard deviations of the parameters for the fixed and sunk cost of operation. The estimated
7Maybe do a multi-variate probit/logit or negative binomial regression later. but for now, OLS
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
fixed cost parameter is less than the sunk cost parameter, indicating that the firm entry cost is
substantially larger than the per-period costs of maintaining operation.
5.3. In-sample Model Performance
To assess the overall fit of the model, we use the estimated parameters to simulate patterns of firm
entry and survival, investment, exporting and product restructuring decision, transition patterns
between the choices, and productivity trajectories for the firms in the sample and compare the sim-
ulated patterns with the actual data. Since each firm’s productivity evolves according to equation
(), we need to simulate each firm’s trajectory of productivity jointly with its dynamic decisions. In
Table 9 we report the actual and predicted percentage of entry, exit, investment, export, product
restructuring and the mean productivity. Overall, the simulations do a good job of replicating these
average data patterns for all three variables.
6. Counterfactuals
6.1. Within Firm Effect
In our model, the determinants of a firm’s entry, exit, export, investment and product restructuring
choices are its current productivity and cost draws. We will isolate the role of current productivity
and the cost shocks on these activities. We do this by calculating the marginal benefit to each
activity. Table 12 reports the partial equilibrium marginal benefits of exporting with different
combinations of productivity and investment with entry and exit rate for calculated for firms optimal
strategies. The first column in the top panel reports the logged values of V (ϕ,X, I,N) with the
optimal investment, export, product restructuring, entry and exit strategy for each productivity
level. The second column reports the logged values of V (ϕ,X, I = 0, N), forcing investment to
be zero, allowing optimal export andproduct restructuring strategies every period, but take entry
and exit rate as given when we calculated for V (ϕ,X, I,N) . The third column reports the logged
values of V (ϕ,X = 0, I,N), forcing profit to be consistent of domestic revenue only and the optimal
investment and product restructuring strategy are recalculated based on domestic profit only. The
fourth column reports the logged value of V (ϕ,X = 0, I = 0, N) forcing both export and investment
to be zero. All the values in the four columns are increasing, reflecting the increase in profits with
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
higher productivity.
The fifth column reports the marginal benefit of exporting for a firm that is allowed to invest
in its future productivity and choose number of products to produce with entry and exit rate as
given. It is positive, reflecting the fact that a firm that does both activities has a higher future
productivity trajectory, and is increasing in current productivity implying that a high productivity
producer is more likely to self select into the export market. The benefit of exporting for a firm
that is not allowed to invest in its future productivity is reported in the sixth column and it is
also positive and increasing in the level of current productivity. Comparing the fifth and sixth
column, we see that the difference between the marginal benefits of exporting with investment and
without investment is positive, implying that the investment decision has important impact on the
return to exporting. This is what we call the market size effect or complementarity in export and
investment. The return to exporting is greatest for middle productivity firms because both low and
high productivity firms investment rate (investment/profit) are less than the middle productivity
investment rate.
Table 13 looks at the marginal benefit of exporting with different combinations of productivity
and product restructuring strategy with entry and exit as given. The third column reports the
logged values of V (ϕ,X, I,N = 1), forcing all firms to produce only one product with optimal
investment and export strategy but taking entry and exit as given before. The fourth column
reports the logged values of V (ϕ,X = 0, I,N = 1), not allowing firms to export nor to produce
more than one product. Again, all the values in the first four columns are increasing reflecting
higher profits with higher productivity. The fifth column is still the marginal benefit of exporting
for firms with optimal strategies in investment and product restructuring. The sixth column is
the marginal benefit of exporting for firms that are only allowed to produce one product. This
is positive and increasing in productivity. The last column in the second panel is the difference
between the marginal benefits of exporting for multi-product firms and firms that are allowed to
produce only one product. This number is positive for middle productivity firms and negative for
high productivity firms. Firms with higher productivity and higher profits, when opening up to
trade, tend to reduce the number of products produced to better focus on their core competency
groups to grab bigger market shares through exporting.
Table 14 looks at the marginal benefit of investment with different combinations of productivity
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
and product restructuring strategy with entry and exit as given. Column five reports the marginal
benefit of investment for firms with optimal product restructuring and export strategies. Column
six reports the marginal benefit of investment for firms that are not allowed to produce more than
one product. The last column reports the difference between the marginal benefits of investment
for multi-product firms and firms that produce only one product. We see the market size effect or
complementarity in investment and product restructuring present because the difference in marginal
benefit is positive for all productivity levels but is greatest for the middle productivity firms.
6.2. Between Firm Effect
We looked at the above counterfactuals with entry and exit rate as given in the previous section, in
this next section, we recompute entry and exit condition for each scenario and look at the general
equilibrium marginal benefits of these activities.
7. Conclusion
This paper estimates a dynamic structural model that captures the relationship between investment,
exporting and productivity for multi-product firms in the presence of endogenous entry and exit.
It characterizes a firm’s joint dynamic decision process for entry, exit, investment, exporting and
number of products as depending on its productivity, and fixed and sunk costs. It also describes
how a firm’s decisions on investment, exporting and product restructuring endogenously affect its
future productivity.
There are five broad conclusions we draw about the sources of productivity evolution among
Spanish firms. First, firm productivity evolves endogenously in response to the firm’s choice to
invest and diversify, but not to the choice to export. An one percent increase in investment raises
future productivity by three percent, and increasing the number of products produced by one raises
future productivity by 6 percent. Second, the marginal benefits of exporting vs. non-exporting in-
crease with firm’s productivity. The marginal benefits of investment versus zero investment is
positive; however it is greater for the middle productivity firms than for both low and high pro-
ductivity firms. The marginal benefits of multi-product versus single product reveals a similar
pattern. This leads to the self-selection of high productivity firms into exporting, investment, and
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
multi-products. When combined with the fact that decisions to diversify and invest lead to endoge-
nous productivity improvements, this further reinforces the importance of self-selection based on
current productivity as the major factor driving the decision to export, invest and produce multiple
products. Third, the cross-partials between exporting and investment, and investment and prod-
uct restructuring are positive for all firms. This suggests that both exporting and investment and
investment and product restructuring augment each other and further reinforce the self-selection
through the complementarity effect. However, the cross partial between exporting and product
restructuring is positive only for low and middle productivity firms and is negative for high produc-
tivity firms. This suggests that when opening up to trade, high productivity firms should decrease
the number of products produced in order to focus on their core competency products and grab a
greater market share through exporting. Fourth, the fixed cost of investment is smaller than the
fixed costs of exporting, which results in a larger proportion of firms choosing to invest than to ex-
port. The larger proportion of firms choosing to invest is also a result of investment having a larger
direct effect on future productivity. Finally, our counterfactual exercises show that a reduction in
trade costs will have a significant positive effect on both the probability and the amount that a
firm exports and invests, while the number of products produced is reduced. These three effects
lead to an overall increase in mean productivity. The combination of larger export markets, and
the firm’s ability to invest and change the number of products they produce to take the advantage
of larger export markets contributes to larger productivity gains.
Overall, our empirical findings emphasize the important role of heterogeneity in productivity
as the driving force in determining a firm’s total revenue and decision to export, invest and produce
multiple products. This is further reinforced by the fact that investment and product restructuring
decisions result in future productivity gains. The model can be extended in several ways. We
can include the distinction between different types of investment and determine the return to each
type of investment. The Spanish firm data includes investment expenditures on R&D, information
computing technologies, industrial machinery, land, building and furniture. We will be able to
look at whether one of the investment tools had a more substantial impact on the productivity. In
addition, we assumed perfect capital markets in this paper. We may explore the role of imperfect
capital market on the return to investment and therefore productivity for different sectors. Firms
in some sectors need to finance a greater share of their costs externally and sectors differ in their
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
endowment of tangible assets that can serve as collateral.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Appendix
Sample Coverage and Data Collection
The ESEE’s population of reference is made up by the firms with 10 or more employees and whichbelong to what is usually known as the manufacturing industry. The geographical scope of referenceis all the Spanish territory, and the variables have a yearly temporal dimension.
One of the most relevant characteristics of the ESEE is its representativeness. The initialselection was carried out combining exhaustiveness and random sampling criteria. In the firstcategory were included those firms which have over 200 employees, and whose participation wasrequired. The second category was composed by the firms which employ between 10 and 200workers, which were selected through a stratified, proportional, restricted and systematic sampling,with a random start. In the first year, 1990, 2,188 firms were interviewed along the above mentionedcriteria. Later special care has been paid to maintaining its representativeness with regard to thepopulation of reference. The effort has been oriented, on the one hand, to reducing as far as possible,the deterioration of the initial sample, trying to avoid the reduction of the firms’ collaboration, andon the other, including each year into the sample all the newly incorporated firms which employover 200 workers, as well as a randomly selected sample which represents around 5
Computation of the Firm’s Dynamic Problem
− 39 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Number of Firms
Median Domestic Revenue
Median Employment
Median Number of Products
2002 610 14.34 23 12003 495 15.96 24 12004 491 16.07 24 12005 716 17.46 22 12006 777 16.55 22 1
Average Domestic Revenue
Average Employment
Average Number of Products
2002 610 89.31 55.77 1.072003 495 110.20 63.09 1.092004 491 122.17 65.07 1.092005 716 137.17 67.57 1.092006 777 144.28 66.27 1.14
Number of firms
Median Domestic Revenue
Median Employment
Median Number of Products
Median Export
Revenue2002 1097 118.10 169 1 47.552003 885 127.06 175 1 52.282004 883 129.60 175 1 55.822005 1195 120.76 156 1 40.042006 1246 105.59 124 1 34.24
Average Domestic Revenue
Average Employment
AverageNumber of Products
Average Export
Revenue2002 1097 618.33 383.5 1.13 400.352003 885 671.04 400.3 1.14 455.222004 883 729.08 400.8 1.14 481.882005 1195 635.56 354.4 1.13 430.032006 1246 631.61 331.5 1.15 452.00
Exporters
Table 1Domestic and Export Revenue (in 100,000 Euros) and Firm Size
Non-exporters
This table provides summary statistics for firm sizes measured in revenues (in 100,000 Euros),average employment and for number of products produced for exporters and non-exporters. Thetop panel consists of median and average measures for non-exporters and the bottom panel consistsof median and average measures for exporters.
− 40 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Year% of Nonzero
Investment
Median Positive
Investment
Average Positive
Investment
% of Nonzero
R&D
Median Positive
R&D Expenses
Average Positive
R&D Expenses
2002 69% 4.13 56.98 11% 4.18 22.392003 68% 5.37 53.55 9% 5.03 18.402004 71% 5.57 68.91 10% 4.68 28.592005 72% 5.31 65.66 11% 3.65 24.372006 67% 5.76 43.01 10% 6.00 10.47
Year% of Nonzero
Investment
Median Positive
Investment
Average Positive
Investment
% of Nonzero
R&D
Median Positive
R&D Expenses
Average Positive
R&D Expenses
2002 88% 57.54 391.25 51% 31.68 226.252003 86% 70.00 428.25 51% 36.90 316.132004 89% 61.75 393.10 52% 35.03 353.362005 90% 56.66 419.94 53% 34.14 314.862006 89% 48.46 416.41 50% 33.70 356.09
N of firms N of firms
610 1097
495 885
491 883
716 1195
777 1246
3,910,000
Non-exporters
Exporters
Table 2Investment and R&D Expenses (in 10,000 Euros)
This table provides summary statistics for firm investment and R&D expenditures (in 10,000 Eu-ros) for exporters and non-exporters. The top panel consists of median, and average investmentand R&D expenditures for non-exporters and the bottom panel consists of median and averageinvestment and R&D expenditures for exporters.
YearN of firms w/ positive Revenue
N of non-operating
firms
N of New Entrants
N of Exits Entry Rate Exit Rate
2002 1707 941 327 0.192003 1380 1268 0 6 0.00 0.002004 1374 1274 0 97 0.00 0.072005 1911 737 634 195 0.33 0.102006 2023 625 307 0.15
Average 1679 969 235.25 156.25 0.14 0.09
625
Table 3Entry and Exit
This table provides number of entry and exit and operating firms in each year.
− 41 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Status Year t Neitheronly
Investmentonly
ExportBoth
All Incumbents 0.11 0.25 0.07 0.57
Neither 0.67 0.29 0.01 0.02only Investment 0.14 0.79 0.01 0.06only Export 0.04 0.03 0.49 0.44Both 0.00 0.02 0.06 0.92
All New Entrants 0.16 0.32 0.08 0.43Neither 0.49 0.40 0.03 0.08only Investment 0.20 0.72 0.00 0.08only Export 0.03 0.00 0.45 0.52Both 0.00 0.03 0.06 0.91
All Exiting Firms 0.27 0.17 0.11 0.45Neither 0.88 0.10 0.02 0.00only Investment 0.44 0.54 0.00 0.02only Export 0.03 0.00 0.42 0.55Both 0.00 0.01 0.04 0.95
Annual Transition Rates for New Entrants
Annual Transition Rates for Firms that Exit in t+2
Table 4Transition Rates for Incumbents, New Entrants, and Exiting Firms
Status Year t+1Annual Transition Rates for Incumbents
This table provides the average annual transition rates for incumbent firms, new entrants andexiting firms in four possible activities: only invest, only export, both, and neither.
Status Year t Neither Only Investment Only Export Both
All Firms 0.11 0.25 0.07 0.57
Neither 0.67 0.29 0.01 0.02
Only Investment 0.14 0.79 0.01 0.06
Only Export 0.04 0.03 0.49 0.44
Both 0.00 0.02 0.06 0.92
Annual Transition Rates for Operating Firms
Status Year t+1
This table provides the average log productivity for new entrants, exiting firms, and incumbentfirms in each year. The productivity measure is constructed using Levinsohn and Petrin (2003)approach.
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Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Parameter Coef St. Error
ρd 0.87 * ( 0.01)
ρx 0.53 * (0.01)
R‐Square 0.99
sample size 4740
Capital R&D
intercept 0.04 (0.13) 0.50 (0.29)
productivity (t‐1) 0.72 * (0.15) 0.30 (0.41)
productivity (t‐1)2 0.03 (0.10) 0.33 (0.20)
productivity (t‐1)3 ‐0.01 (0.02) ‐0.05 (0.03)
investment (Ii,t‐1) 0.03 * ( 0.01) 0.03 * (0.01)
export (Xi,t‐1) 0.00 ( 0.02) 0.03 (0.05)
product restr. (Ni,t‐1) 0.06 * ( 0.01) 0.06 * ( 0.01)
R‐Square 0.98 0.97
sample size 4740 2121
Table 1
Variable Cost
Table 2
Productivity Evolution
Investment measured as:
This table provides the estimated coefficients for equation () and (). The top panel provides theestimates for elasticity of substitution for domestic and export market, respectively. The bottompanel provides the estimates for the productivity evolution. *** indicates significance at 1%. ** at5%, * at 10%.
− 43 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Parameter Mean St. Dev. ThousandsEntry sunk cost 19.7 2.25 € 359,000Domestic fixed cost 12 0.41 € 160Product fixed cost 11 0.36 € 59Export fixed cost 13.5 0.45 € 730Investment Fixed Cost 10.4 0.32 € 32d (investment cost) 1 0.01Avg sell-off value 16 0.92 € 8,900
Table 3Dynamic Parameter Estimates
This table provides the estimated coefficients for equation () and () in reduced form. The toppanel provides the estimates for export decision in a probit model using productivity measuresconstructed from before. The middel panel provides the estimates for exit decision in a probitmodel. The last panel provides estimates from an OLS regression of number of products on firmproductivities. *** indicates significance at 1%. ** at 5%, * at 10%.
Parameter Mean St. Dev. In EurosEntry sunk cost 19.7 2.25 359 millionDomestic fixed cost 12 0.41 .16 millionProduct fixed cost 11 0.36 59 thousandExport fixed cost 13.5 0.45 .73 millionInvestment Fixed Cost 10.4 0.32 32 thousandd (investment cost) 1 0.01avg sell-off value 16 0.92 8.9 million
Table 8Dynamic Parameter Estimates
This table provides the estimated coefficients for the dynamic parameters in the model and thecorreponding dollar values for these estimates.
− 44 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
export participation Average Productivityactual 0.63 Actual 2.22predicted 0.62 Predicted 2.36
Investment Exit rateActual 15.41 Actual 0.09Predicted 15.75 Predicted 0.06
Entry rateActual 0.15Predicted 0.07
Table 9In-Sample Performance
This table shows the in-sample performance for estimated static and dynamic parameters.
− 45 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
This graphs shows that investment, export and productivity are all correlated.
− 46 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
This graphs shows how the investment, export, and profits change when a country is opening upto trade. The top panel shows the change in profits when a country is opening up to trade. Thebottom panel shows the change in investment profile when a country is opening up to trade. ϕit isthe productivity. ϕA
∗i is the productivity cut-off in autarky below which firms cannot operate. ϕCT
∗i
is the productivity cut-ff when a country goes from autarky to trading, below which firms cannotoperate. ϕCT
∗ix is the productivity cut-off for exprting firms, below which firms cannot export.
− 47 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
productivity V(X,I,N) V(X,I=0,N) V(X=0,I,N) V(X=0,I=0,N) MBEMBE (I=0)
MBE -MBE(I=0)
1.9 16.44 16.44 16.44 16.44 0.00 0.00 0.002 16.73 16.48 16.66 16.48 0.08 0.00 0.08
2.1 16.96 16.53 16.80 16.53 0.16 0.00 0.162.2 17.27 16.57 16.98 16.57 0.29 0.00 0.292.3 17.65 16.66 17.21 16.66 0.43 0.00 0.432.4 18.08 16.84 17.49 16.80 0.59 0.04 0.552.5 18.53 17.14 17.79 17.02 0.74 0.11 0.622.6 18.98 17.55 18.11 17.32 0.87 0.23 0.642.7 19.43 18.13 18.49 17.76 0.94 0.37 0.572.8 19.77 18.81 19.00 18.29 0.77 0.51 0.262.9 20.40 19.53 19.57 18.87 0.84 0.66 0.183 21.10 20.30 20.16 19.50 0.94 0.80 0.14
Table 12 Investment and Export Complementarity
This table shows the investment and export complementarity. All values are in logs. MBE ismarginal benefit of exporting and is defined as V(X,I,N)-V(X=0,I,N), where V(X,I,N) is the valuefunction when all three choices, X, I, and N are chosen optimally and the dynamic parameters arecomputed using maximum likelihood estimator. V(X=0,I,N) is the value function when export isrestricted to 0 and I and N are chosen optimally with entry and exit rate fixed as in V(X,I,N).MBE (I=0) is the marginal benefit of exporting when investment is restricted to 0 and is defined asV(X,I=0,N)- V(X=0, I=0, N). The cross partial between I and X is defined as MBE - MBE (I=0).
− 48 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Investment Complementarity
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.9 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3log productivity
log
V
MBE MBE(I=0)
I complementarity
This graph shows the investment and export complementarity. The thin continuous line plots theMBE defined before, the dotted line plots the MBE (I=0), and the dashed line plots the crosspartial between investment and export, or what we call investment complimentarity.
− 49 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
productivity V(X,I,N) V(X=0,I,N) V(X,I,N=1) V(X=0,I,N=1) MBEMBE (N=0)
MBE-MBE(N=0)
1.9 16.44 16.44 16.44 16.44 0.00 0.00 0.002 16.73 16.66 16.67 16.63 0.08 0.04 0.04
2.1 16.96 16.80 16.83 16.73 0.16 0.09 0.072.2 17.27 16.98 17.04 16.86 0.29 0.18 0.112.3 17.65 17.21 17.32 17.01 0.43 0.30 0.132.4 18.08 17.49 17.67 17.19 0.59 0.48 0.112.5 18.53 17.79 18.06 17.39 0.74 0.66 0.072.6 18.98 18.11 18.47 17.75 0.87 0.71 0.162.7 19.43 18.49 18.86 18.20 0.94 0.66 0.282.8 19.77 19.00 19.49 18.72 0.77 0.77 0.002.9 20.40 19.57 20.18 19.27 0.84 0.91 -0.073 21.10 20.16 20.93 19.82 0.94 1.11 -0.17
Table 13 Multiproduct and Export Complementarity
This table shows the multi-product and export complementarity. All values are in logs. MBE ismarginal benefit of exporting and is defined as V(X,I,N)-V(X=0,I,N), where V(X,I,N) is the valuefunction when all three choices, X, I, and N are chosen optimally and the dynamic parameters arecomputed using maximum likelihood estimator. V(X=0,I,N) is the value function when export isrestricted to 0 and I and N are chosen optimally with entry and exit rate fixed as in V(X,I,N).MBE (N=0) is the marginal benefit of exporting when number of products is restricted to 1 and isdefined as V(X,I,N=1)-V(X=0, I, N=1). The cross partial between N and X is defined as MBE -MBE (N=1).
− 50 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Multiproduct Complementarity
-0.40
-0.20
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.9 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3
log productivity
log
V
MBE MBE(N=1) Multiproduct complementarity
This graph shows the multi-product and export complementarity. The thin continuous line plotsthe MBE defined before, the dotted line plots the MBE (N=1), and the dashed line plots the crosspartial between multi-product and export, or what we call multi-product complimentarity.
− 51 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
productivity V(X,I,N) V(X,I=0,N) V(X,I,N=1) V(X,I=0,N=1) MBIMBI
(N=1)MBI -
MBI(N=1)
1.9 16.44 16.44 16.44 16.44 0.00 0.00 0.002.0 16.73 16.48 16.67 16.48 0.25 0.19 0.062.1 16.96 16.53 16.83 16.52 0.43 0.30 0.132.2 17.27 16.57 17.04 16.56 0.70 0.48 0.222.3 17.65 16.66 17.32 16.64 0.99 0.67 0.312.4 18.08 16.84 17.67 16.81 1.24 0.86 0.382.5 18.53 17.14 18.06 17.07 1.39 0.99 0.402.6 18.98 17.55 18.47 17.48 1.43 0.99 0.442.7 19.43 18.13 18.86 18.04 1.30 0.82 0.482.8 19.77 18.81 19.49 18.71 0.97 0.78 0.192.9 20.40 19.53 20.18 19.44 0.87 0.74 0.133.0 21.10 20.30 20.93 20.22 0.80 0.72 0.08
Table 14 Investment and Multiproduct Complementarity
This table shows the investment and multi-product complementarity. All values are in logs. MBI ismarginal benefit of investment and is defined as V(X,I,N)-V(X,I=0,N), where V(X,I,N) is the valuefunction when all three choices, X, I, and N are chosen optimally and the dynamic parameters arecomputed using maximum likelihood estimator. V(X,I=0,N) is the value function when investmentis restricted to 0 and X and N are chosen optimally with entry and exit rate fixed as in V(X,I,N).MBI (N=1) is the marginal benefit of investment when number of products is restricted to 1 andis defined as V(X,I,N=1) - V(X, I=0, N=1). The cross partial between I and N is defined as MBI- MBI (N=1).
− 52 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Multiproduct and I
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.9 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3log productivity
log
V
MBI MBI(N=1) Multiproduct complementarity
This graph shows the investment and multi-prodcut complementarity. The thin continuous lineplots the MBI defined before, the dotted line plots the MBI (N=1), and the dashed line plotsthe cross partial between investment and multi-product, or what we call investment-multi-productcomplimentarity.
− 53 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
Table
Su
mm
ary
of
the s
am
ple
’s e
volu
tion
in
th
e y
ears
19
90
-20
08
1
99
1
19
92
1
99
3
19
94
1
99
5
19
96
1
99
7
19
98
1
99
9
20
00
2
00
1
20
02
2
00
3
20
04
2
00
5
20
06
2
00
7
20
08
1. C
urr
en
t sa
mp
le
2188
2059
1977
1869
1876
1703
*
1716
1920
1776
1754
1870
1724
1708
1380
1374
1911
2023
2013
1
.1 F
irm
s w
hic
h
an
swer
1888
1898
1768
1721
1693
1584
1596
1764
1631
1634
1693
1635
1380
1374
1277
1716
1892
1853
1
.2 D
isap
pear1
62
52
72
53
51
28
35
18
45
38
20
18
51
4
17
35
30
57
1
.3 D
o n
ot
collab
ora
te
187
62
124
45
55
33
54
22
35
24
0
12
88
0
12
14
18
10
1
.4 N
o a
ccess
2
51
47
13
50
77
58
31
116
65
58
157
59
189
2
68
146
83
93
2. R
eco
vere
d3
129
99
73
46
0
3
2
3. En
trie
s in
th
e c
urr
en
t year
42
79
101
56
9
132
324
12
123
236
31
0
0
0
588
307
118
154
Nu
mb
er
of
reco
rd o
n f
ile
2359
2438
2539
2595
2604
2736
3060
3072
3195
3431
3462
3462
3462
3462
4050
4357
4475
4629
Not
as:
1.
Clo
sure
s, f
irm
s in
liq
uid
ation,
chan
ge
to a
non-m
anufa
cturing a
ctiv
ity,
dis
appea
rance
thro
ugh m
erger
or
acquis
itio
n.
2.
Can
not
be
found,
pro
visi
onal
clo
se-u
p.
3.
In 1
991 t
hey
are
lar
ge-
size
d f
irm
s to
whic
h t
he
ques
tion
nai
re w
as a
lrea
dy
subm
itte
d in 1
990,
but
whic
h d
id n
ot a
nsw
er it.
In 1
994 it
is m
ade
up o
f la
rge-
size
d firm
s w
hic
h h
ad fill
ed t
he
ques
tion
nai
re b
efor
e but
whic
h a
t so
me
tim
e th
ey s
topped
doi
ng it.
*
Incl
udes
a c
om
pan
y w
hic
h d
id n
ot
colla
bora
ted in 1
995 b
ut
whic
h c
olla
bora
ted in 1
996.
The table shows the evolution of the sampled firms during the period 1990-2007− 54 −
Product Restructuring, Exports, Investment, and Growth Dynamics Leilei Shen
1
SAMPLE COVERAGE ESEE 2005*
Less than
20 21 to 50 51 to 100 101 to 200 More than
200 Meat-processing industry 1.54% 3.03% 2.04% 14.29% 32.00%Foodstuffs and tobacco 2.42% 3.10% 3.97% 5.32% 38.75%Drinks 3.32% 3.40% 7.41% 23.81% 41.03%Textiles 3.06% 3.75% 6.98% 16.04% 42.62%Leather and footware 3.03% 4.67% 5.63% 14.81% 14.29%Wood industry 1.37% 3.25% 7.69% 16.67% 50.00%Paper 3.53% 3.38% 6.82% 14.29% 60.53%Editing and printing 1.98% 2.96% 6.67% 7.08% 40.32%Chemical industry 2.25% 4.28% 6.61% 11.03% 39.16%Rubber and plastics 3.09% 2.95% 5.79% 12.90% 46.43%Non-metallic minerals products 2.35% 3.34% 2.60% 10.18% 43.40%Iron and steel 2.12% 3.02% 5.65% 14.29% 48.57%Metallic products 2.01% 2.88% 5.31% 7.45% 41.67%Machinery and mechanical goods 2.41% 3.27% 5.42% 12.84% 51.95%Office machinery, computers, processing, optical and similar 1.54% 5.63% 13.64% 4.55% 45.45%Electrical and electronic machinery and material 3.06% 3.95% 4.81% 11.70% 45.83%Motor vehicles 2.74% 3.85% 6.19% 12.66% 44.85%Other transport material 1.57% 6.15% 13.04% 44.00% 31.58%Furniture 2.45% 3.31% 4.86% 12.00% 50.00%Other manufacturing 3.06% 2.73% 2.70% 9.38% 40.00%Total 2.36% 3.37% 5.44% 11.40% 42.95% * Sample coverage, calculated with respect to the Spanish Social Security Census
The table shows the sample coverage.
− 55 −